Combined blackboard and writing-desk



(No Model.) 3 Sheets-Sheet 2.

0. M. MITCHELL.

COMBINED BLAGKBOARD AND WRITING DESK.

No. 366,596. Patented July 12, 1887.

011's 7 777170116 7] I JV 'VEJV' TOR W1 TJVESSES Attorney (No Model.) 3 Sheets-Sheet 3. O. M'. MITCHELL.

COMBINED BLACKBOARD AND WRITING DESK. No. 366,596.

Pat ented July 12, 1887.

W1 TNEIS'ISES N. PETERS. Phalo Li|hograpnon Wmhmgtnn. D. c.

UNITED STATES PATENT Fries.

OTIS M. MITCHELL, OF MARATHON, NE'W YORK.

COMBINED BLACKBOARD AND WRITING-DESK.

SPECIFICATION forming part of Letters Patent No. 366,596, dated July 12, 1887.

Application filed Februaryz'l, 1887'. Serial No. 226,635. (No model.)

To aZZ whom it may concern:

Be it known that l, OTIS M. MITCHELL, a citizen of the United States of America, residing at Marathon, in the county of Cortland and State of New York, have invented certain new and useful Improvements in Blaekboards and XVriting-Desks; and I do hereby declare the following to be a full, clear, and exact description of the invention,sueh as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to letters or figures of reference marked thereon, which form a part of this specification.

My invention relates to certain new and useful improvements in portable blackboards and desks which-are adapted for home and school use; and my invention consists in the construction and combination of the parts, whereby I provide a cheap, portable, and convenient blackboard or dcsk,whieh may be eitherstood upon suitable supporting-legs or hung against the wall, as will be hereinafter fully set forth, and specifically pointed out in the claims.

In the accompanying drawings,which illustrate my invention, Figure l is a perspective view of my improvement, showing the blackboard inclined so as to expose the copy-sheet. Fig. 2 is a perspective view showing my improvement arranged to be used as a desk, the blackboard being supported in an almost horizontal position. Fig. 3 is a vertical sectional view showing the blackboard in a vertical position in full lines and inclined in dotted lines. Fig. 4 is a detail perspective view of "one end of a hinged shelf. Fig. 5 is a detail perspec tive view of one of the supporting-arms. Fig. 6 is a perspective view of one of the guidestrips for the blackboard. Fig. 7 is a view showing the manner of formingmarks orlines upon the board, and Fig. 8 is a detail view of the bars having laterally-projecting portions which are attached to the blackboard.

A refers to the blackboard proper, which is constructed in the usual manner, the edges thereof being provided with metallic strips a, which will prevent the board warping. Both sides of the aforesaid board are coated with asuitable composition, and upon the lower edge is secured a grooved or recessed strip,e, which serves as a chalk-holder. The opposite side of the board from the chalk-holder a has attached thereto, near its upper corners, metallic bars I), the ends of which project at right angles with the body portion and are provided with pins which project outwardly.- The blackboard is also provided at suitable points near its center with plates b, which have their center portions struck up so as to form sockets, in which the bent ends of the pivoted spring-arms may be placed,as will be hereinafter fully set forth.

The frame B, to which the blackboard can be attached in its various positions, consists of vertical side pieces, B and B to which is suitably attached a backing, O, which is pro vided near its upper ends with key-hole slots 0 c, which provide a means for supporting the frame against the wall. At suitable points the side pieces are connected to each other by transverse strips 0' G and at the bottom of the side pieces by a bottom board, C, which is provided longitudinally with a recess or depression, in which pens, pencils, or other suit able articles may be placed, and at the front of the frame is attached a transverse board, C, between which and the blackboard are placed a series of partition-boards.

D refers to a suitable frame, in the ends of which are mounted rollers d d, the ends of said rollers adjacent to the side piece, B, having operating handles or knobs,whieh are of such a size that they may be readily passed through the openings d in the vertical side piece, '13. The frame I) is of less length than the space between the side boards and of less depth than the distance between the back board and the frontedge of the horizontal boards G and C", and when the frame D is placed in position it will rest upon the board 0' and against the back board, 0. Between the frame D and the vertical side boards are placed suitable blocks, against which the edges of the frame ,D will abut.

It will be observed that by constructing the frame D as shown it may be readily removed from the compartment provided therefor and a new frame substituted in its place, thus obviating the necessity of unwinding and removing the copy from the rolls when it is dcsired to copy material not shown on the roll. Therefore, when it is desired to change the copy-sheet, it is only necessary to substitute a new frame.

The edges of the boards 13 and B have at tached thereto a vertical strip or batten, E, as shown in Fig. 6, which strips will have a projecting portion, 0, with which the projecting pins on the bars I), which are attached to the blackboard, will engage. These strips E may be attached to the side pieces by asingle screw, and the corners can be bent so as to engage with the inner sides of the boards B and B", so as to prevent said strips turning. The space between the bottom-board, O, of the frame and the horizontal board (3 is partly occupied by a hinged compartment, F, which consists of end pieces, ff, between which are secured partition-boards, said partition-boards and end pieces being attached tothe strips f and f which form the front and bottom board when the compartment is placedin a vertical position, as shown in Fig. 3, and the bottom and back board when placed in the position shown in Fig. 2. The boardf of this compartment is provided centrally with a suitable turn-button, which engages with arecess in the under side of the board 0 for holding said compartment in a closed position; and the corners adjacent to the side boards have metallic strips 9 securely attached thereto, while the edge of the board f is slightly cut away, so as to allow a pin, to be passed under said metallic strip and occupy a position on a line with the corner of the board f, upon which the compartment turns, so that a comparatively small space will exist between the back board of the frame and thecompartment when placed either in a vertical or horizontal position- These pins 9 pass through perforations in metallic plates attached to vertical strips G, which are secured to the side pieces and back board of the frame, and the lower ends of these strips G form pivots forthe horizontally-swinging arms H, as shown in Fig. 5.

The arms H, as hereinbefore stated, are pivoted between the lower ends of the strips G and the bottom board, 0, and these arms are provided with projecting portions 71 which are preferably made of malleable iron, the ends of which are bent downwardly, so as to engage the upwardly-projecting portions of the bars 6, or the upper edge of the blackboard when placed beneath the same. The arms H are also provided with recesses h, in whichthe pins of the bars I) may lie when the board is used in a position shown in dotted lines in Fig. 3.

To the side boards, '13 and B at'a point nearly opposite the lower end of the strips G, are pivotally attached spring-arms I, the free ends of which are bent at right angles, so as to engage the curved plates 1), attached to the blackboard.

The support for the blackboard consists of legs, which are made up of barsK, K, and.

K, which are connected to each-other, the legs K and K being attached to the center of the'bar K, and the ends of said strip are provided with slots, the lower ends of which may be slightly enlarged, so thatprojecting pins Z on the legs will engage with said slots. The upper portion of this rod vK is provided with key-hole slots, with which projecting pins attached to the side boards engage. 'By constructing the legs as hereinbefore described they can be readily attached and detached from the frame, and they will fold automatically, so as to occupy but little space.

I propose to provide either one or both surfaces of the blackboard with minute dots or depressions, which are formed in the surface of the blackboard by a suitable instrument having a rounded point, thus forming in the surface of the blackboard semi-spherical depressions. These depressions are arranged in series, so as to form lines, letters, or figures, and the characteristics of these depressions are, that though they may be visible at a short distance from the surface of the board they will not be visible at a greater distance or mar the effect of lines drawn on the surface of said board, and

when the chalk-marks are erased from said board the eraser will enter these semispherical depressions, so as to remove the chalk-dust therefrom. Heretofore it has been proposed to draw lines or print lightly upon the board;

but these lines or printed marks are visible at a greater distance from the board than is desirable.

When it is desired to place the board in a vertical position, as shown in Fig. 3, the aforesaid board is placed at an angle'across thenpper space in the frame, and the upper edge is then brought to a horizontal position, when the projecting pins on the bars I) will engage with the vertical strips E, and hold the upper edge securely to the frame, the lower edge of the board being secured to the frame by a suitable hook.

When it is desirable to place the board at an anglewith the frame, as shown in Fig. 1, so as to expose the copy, the spring-arms I are caused to engage the plates b, and the board is let fall until the projecting portions of the bars I) and the pins thereon engage with the upper edge of the transverse board 0 adjacent to the recess 0, formed therein.

IQS

When it is desirable to use the blackboard The projecting portions or bars 71, are of light or cheap construction, so that should excessive weight or pressure he placed upon the surface of the board when it is used as a desk or otherwise thesebars would give way before any of the other parts, and as they are cheaply made they could be replaced without great expense.

It will be observed that the board A may be placed either side up when used as a desk, and when the same is used as a desk the compartment can be folded down, so as to bring papers or such materials as may have been placed therein to an accessible position.

This invention will be found particularly useful either for home or school use, and can be used both as a desk and blackboard in its various positions, and the board will be held firmly in any ofthepositionsin which it may be placed, and that as it is free from any com plicated or loose parts it is not liable to get out of order, or any of the parts become lost, and

can be readily set up in any position in which the person using the same may desire.

I claim- 1. In a combined blackboard and writ-ingdesk, a frame provided with two or more compartments, said main frame having perforations in one of its side pieces, in combination with an independent and removable copyholder frame, adapted to be removed from one of said compartments or maintained therein, so ,that the operating-knobs of the rollers thereof will project through the main frame, substantially as shown, and for the purpose specified.

2. In a combined blackboard and writingdesk, a main frame provided near its upper portion with vertical guide-strips E and near its lower portion with supports, a board having bars I), with laterally-projecting pins formed thereon, attached near the edge of the board, so as to engage with the guide-strips E and plates 1), with which the pivoted arms I engage, so as to maintain the board in an inclinedposition with respect to the main frame, substantially as shown.

3. In a combined writing-desk and blackboard, the main frame, having pivoted thereto horizontally-swinging arms, with strips h and recesses h, in combination with the board A, having bars I), with laterally-projecting pins attached thereto, wherebysaid board can be maintained bysaid arms in an almost horizontal position with either side uppermost, substantially as shown.

t. A blackboard provided on its surface with semi-spherical depressions arranged so as to form lines, figures, or letters, substantially as and for the purpose specified.

5. In combination with the main frame, provided with horizontally-swinging arms, said arms having projecting portions h at tached thereto, and a board adapted to be supported by said arms and projecting portions h, substantially as shown, and for the purpose set forth.

6. In a blackboard or writing-desk provided with pins which project from the side pieces of the main frame, supporting-legs consisting of a bar, K, having key-hole slots, which engage with the projecting pins of the main frame, legs K K, attached at, their upper ends to the bar K by spring-plates, and a latclrbar, L, pivoted to the bar K and adapted to engage with projecting pins sccur'edto the legs, substantially as shown, and for the purpose set forth.

7. In a combined blackboard and writingdesk, the side strips, B and Bflhaving attached thereto metallic strips E, having one of the Vertical edges bent at right angles and the corners bent so as to engage the inner sides of the side pieces, transverse board 0 having notches c, a board, A, having bars I) attached near the upper edge thereof, the ends of said bars having upwardly and outwardly projecting portions, which are adapted to engage with the inturned edges of the strips E and bear upon the portion of the board C adjacent to the notches therein, and arms for holding the board in an inclined position with respect to the main frame, substantially as shown, and for the purpose set forth.

In testimony whereof I affix my signature in presence of two witnesses.

OTIS M. MITCHELL.

Vitnesses:

E. W. J OIINSON, \VILLIAM SEL'BY. 

